Prosthetic foot

ABSTRACT

A prosthetic foot with a base spring with a forefoot area and a heel area, a connecting means arranged above the base spring and used to fasten the prosthetic foot to a prosthesis, and a frontal support, at the upper end of which the connecting means is arranged and which, at its lower end, is secured on a torsion element that can twist about the longitudinal axis of the prosthetic foot. The torsion element is designed as a leaf spring arrangement secured to the base spring at one end in the heel area or in the forefoot area.

TECHNICAL FIELD

The invention relates to a prosthetic foot with a base spring with aforefoot region and a heel region, a termination apparatus, arrangedabove the base spring, for affixing the prosthetic foot to a prosthesisand a frontal support, at the upper end of which the connectionapparatus is arranged and the lower end of which is secured to a torsionelement which can be twisted about the prosthesis longitudinal axis. Theinvention likewise relates to a prosthetic foot with a base spring witha forefoot region and a heel region, and a connection apparatus,arranged above the base spring, for affixing the prosthetic foot to aprosthesis.

BACKGROUND

DE 10 2006 004 132 A1 describes an artificial foot with an elastic solestructure, extending from a heel region to a toe region, with alongitudinal axis, a connection to a below-knee part, an upwardlyextending upper support structure and an elastic connection elementarranged between the upper support structure and the sole structure. Theupper support structure is, in the longitudinal direction, connected tothe sole structure approximately in the approximately in the center ofthe foot by means of a coupling arrangement, which allows a relativetilt movement between the sole structure and the support structure.Here, the distance between the support structure and the sole structurein the center of the coupling arrangement remains constant, at leastwhen loaded by weight when the patients are standing. The jointarrangement consists of an elastic polymer cylinder, which supportsitself on the sole structure with a lower end face and on the lower sideof the support structure with an upper end face. A pin arrangementcomplements the polymer cylinder and has spherical heads on both of itsends, which spherical heads support themselves firstly on the solestructure and secondly on the support structure and increase thestability of the connection. It is likewise possible for the jointarrangement in the form of a spherical cap to be formed with acorrespondingly interacting ball socket in order thus to establish thetiltable connection between the support structure and the solestructure.

The artificial foot in accordance with the prior art renders it possibleto improve the rollover action during walking; moreover, well definedstatics in standing are present as a result of a forwardly displacedforce transmission point. However, only small restoration forces can berealized by the elastic polymer cylinder, and so the spring propertiesof the artificial foot during walking have to be realized only by thesole structure. Moreover, as a result of the polymer cylinder, use ismade of components susceptible to wear-and-tear, which is detrimental tothe precision of the force transmission.

SUMMARY

It is an object of the present invention to provide a prosthetic footwhich offers improved options for adjusting the rollover behavior of theprosthetic foot and precise statics during standing, even in the case ofvariable conditions underfoot.

According to the invention, this object is achieved by a prosthetic footwith the features of the main claim or the coordinate claim.Advantageous embodiments and developments are listed in the dependentclaims, the description and the figures.

The prosthetic foot according to the invention with a base spring with aforefoot region and a heel region, a connection apparatus, arrangedabove the base spring, for affixing the prosthetic foot to a prosthesisand a frontal support, at the upper end of which the connectionapparatus is arranged and the lower end of which is secured to a torsionelement which can be twisted about the prosthetic-foot longitudinal axisprovides for the torsion element to be configured as a leaf springapparatus, secured at one end either in the heel region or in theforefoot region. As a result of clamping the torsion element at one endin the heel region, it is possible for there also to be a bend about anaxis extending transversely with respect to the longitudinal axis of thefoot in addition to a twist about the longitudinal axis of the foot whenthe heel region is set down, such that the torsion element, in additionto the option of an angular compensation in the walking direction, alsoprovides an additional spring element in order to enable the heel to beset down relatively softly. After the forefoot region is set down andwhile the prosthetic foot rolls over, the free, front end of the torsionelement then rests against the base spring such that this results instiffening by a parallel connection of the base spring and the torsionelement. The prosthetic foot according to the invention renders itpossible to convert the well-defined statics by means of the forwardlydisplaced force transmission point into a dynamic construction and inthis case simultaneously ensure the standing stability, even in the caseof changes underfoot or in the case of different shoes. The torsionelement, which in general prevents a displaceability or deformabilityalong the longitudinal extent of the prosthetic foot, is used to keepthe resting point of the support structure on the sole structureprecisely constant in space, without it being possible for the forcetransmission position to change due to wear-and-tear.

In an alternative embodiment of the invention, provision is made for theprosthetic foot to be equipped with a base spring with a forefoot regionand a heel region, and a connection apparatus, arranged above the basespring, for affixing the prosthetic foot to a prosthesis, wherein theconnection apparatus is secured to a torsion element which can betwisted about the prosthetic-foot longitudinal axis, which torsionelement is configured as a leaf spring apparatus, secured at one end tothe base spring in the heel region. The torsion element as a leaf springis only secured in the heel region of the base spring, and so, when theheel is set down, the front end of the torsion element distances itselffrom the base spring and increases the distance in the front region ofthe torsion element from the base spring. Here, the connection apparatusis arranged in front of the point where the torsion element is affixedto the base spring such that the torsion element likewise has aresilient effect as well when the heel is set down. During the course ofthe further standing phase, the base spring lowers for complete contacton the ground. Subsequently, the torsion element is lowered further inthe direction of the base spring until the front end of the torsionelement rests on the upper side of the base spring. As the load on theforefoot increases, both the base spring and the torsion element bendtogether in the direction of the ground such that the base spring andthe torsion element act together and are connected in parallel. Here,the torsion element rests on the upper side of the base spring and theforces acting on the rear end of the torsion element are transmitted onto the base spring in the attachment means, e.g. screws, by means ofwhich the torsion element is affixed to the base spring. In order toprevent hard impact of the front part of the torsion element on the basespring, provision is made for a cushioning element, for example foam orthe like. As a result of securing the torsion element at one end in theheel region, both twisting about the longitudinal axis of the foot andcushioning about an axis extending in the medial/lateral direction arepossible, and so it is possible to achieve a simple adjustment of thebase spring to uneven underfoot conditions as well when standing, i.e.during the standing phase.

In the case of one-ended linkage of the torsion element in the forefootregion, there is a parallel connection of the base spring and thetorsion element when a heel is set down, and so a stable foot set-downis ensured. During the course of the rollover movement, the torsionelement can, during increasing forefoot load, be bent open about an axistransverse to the longitudinal direction such that an additional springis available for adjusting the elasticity of the prosthetic foot. Theability of the torsion element to twist changes differently during thestanding phase, depending on the point of the linkage.

As a result of the one-ended linkage of the torsion element, the otherend, which is not secured to the base spring, can distance itself fromthe base spring during a flexural load, i.e. increase the distancebetween the base spring and the torsion element, or else reduce saiddistance if, in the initial position, there is a displacement path inthe direction of the base spring.

A clear space can be formed between the base spring and the torsionelement in order firstly to enable a displacement in the direction ofthe base spring and secondly, in the case of a platform or cushioningbetween the base spring and the torsion element, to provide for anadditional bend of the torsion element, even in the state where thetorsion element rests against the platform or cushioning.

A buffer element can be arranged between the torsion element and thebase spring in order to damp the impact of the torsion element on thebase spring during the rollover or when setting down the foot. Thebuffer element can have a shape which allows twisting of the torsionelement, even in the state where it rests against the base spring, forexample a rounded shape or designed as a web, such that it is possiblefor the torsion element to tilt relative to the base spring. As analternative to this, the contact area between the torsion element andthe base spring can have a planar design such that no torsion ispossible during the standing phase when the torsion element restsagainst the base spring. This provides greater stability of theprosthetic foot.

As a result of the configuration of the torsion element as a leaf springapparatus, i.e. as a single part or multipart leaf spring, provision ismade for the torsion element to be able to be twisted about an axisextending in the medial/lateral direction such that the individualspring elements, namely the torsion element and the base spring, becomeactive in a staggered fashion.

The frontal support, which leads from the connection apparatus, forexample a connection adapter, to the torsion element can likewise beconfigured as a spring or as a spring package in order to provide anadditional spring component by means of which an adaptation to therespective prosthetic-foot user and the respective field of use or thepreferences of the prosthetic-foot user can be set. The frontal supportis preferably configured as a leaf spring or as a leaf spring package.

The frontal support can be configured in such a way that it can betwisted about a vertical axis such that, is the standing phase, there isa certain amount of resilience, even in the case of a rotational loadabout a vertical axis, such that, even in the case of complete contactof the prosthetic foot with the ground underfoot, a rotatability andresilience about a vertical axis are possible. As a result of this, thecomfort of the behavior of the prosthetic foot during walking orstanding can be increased for a prosthetic-foot user.

In the walking direction, the frontal support preferably ends in frontof the connection apparatus, i.e. approximately in the region in whichthe force vector of the ground reaction force runs through theprosthetic foot during standing. The frontal support therefore endsapproximately three to five centimeters from the connection apparatus inthe anterior direction.

The frontal support can support itself on the base spring in a supportregion, which is situated in front of the connection apparatus in thewalking direction. The support region can be equipped by the torsionelement or by webs, cushions, dampers or the like below the torsionelement or on the base spring. The frontal support can support itself onthe base spring in the center of the base spring, wherein a centralsupport is advantageous both in the longitudinal direction and in thetransverse direction.

A heel spring, which, as an additional spring element, enables force tobe taken up during the heel strike, can be arranged on the base spring.A damping element can be arranged between the base spring and the heelspring in order to convert the kinetic energy when the foot is set downinto deformation energy or heat.

A damping element or a resilient element, which is supported on the basespring or on the torsion element in the heel region of the base spring,can be arranged on the connection apparatus or on the upper end of thefrontal support. Such an embodiment is provided in particular if thetorsion element is secured at one end in the heel region. As a result,there can be additional damping of the heel strike. The damping elementcan be configured as a fluid damper, in particular as a hydraulic damperor pneumatic damper, in order to be able to achieve simple adjustabilityof the degree of damping. Fluid dampers can be set separately both inthe rebound travel and in the compression travel such that a variablecompression behavior and rebound behavior of the connection apparatus orof the compression piston can be ensured. In addition to the betteradjustability, the damper has the property of not building up any forcesstatically. Hence the foot can repeatedly adapt itself to the conditionsunderfoot or to the shoes when standing; all that act are therestoration forces of the relatively flexible torsion spring.

The damping element has at least one multi-axially movable joint, suchthat, in addition to pivoting about a medial/lateral axis duringcompression, there can, for example, also be a rotation about ananterior/posterior axis in order to be able also to allow twisting ofthe torsion element and hence tilting of the connection apparatusrelative to the base spring. The multiaxial joint is preferably formedon a mount point on the connection apparatus or the base spring suchthat the damping element itself can perform a stable linear motion.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following text, an exemplary embodiment of the invention will beexplained in more detail on the basis of the attached figures. The samecomponents are denoted by the same reference signs. In detail:

FIG. 1 shows a perspective overall view of a prosthetic foot;

FIG. 2 shows a side view with a partly cut heel;

FIG. 3 shows a sectional illustration along B-B in FIG. 2;

FIG. 4 shows a side view of a variant; and

FIG. 5 shows a variant of the prosthetic foot without frontal support.

DETAILED DECSRIPTION

FIG. 1 shows a prosthetic foot 100 in a perspective oblique plan view.The prosthetic foot 100 has a base spring 23 with a forefoot region 231and a heel region 232. The base spring 23 is preferably manufacturedfrom a fiber composite material, more particularly a carbon fibercomponent. The base spring 23 has an elongate configuration, wherein theprosthetic-foot longitudinal axis 230 extends in the longitudinaldirection. The base spring 23 has a substantially straight design; aslight curvature is provided in the forefoot region 231 in order tofacilitate a rollover action of the prosthetic foot 100.

A heel spring 24 is arranged on the base spring 23 in the heel region232. The heel spring 24 is likewise made of a fiber composite material,more particularly of a carbon fiber material. The heel spring 24 can beaffixed to the base spring 23 in an interchangeable fashion. A clearspace which tapers off in the walking direction is provided between theheel spring 24 and the base spring 23, in which clear space a dampingelement 32 is arranged. This damping element can also be used to securethe heel spring 24 to the base spring 23.

A torsion element 28 in the form of a leaf spring is arranged on theupper side of the base spring 23. The torsion element 28 is secured inthe heel region 232 of the base spring 23; the way in which it issecured will be explained on the basis of FIG. 2. The torsion element 28is only affixed to the base spring 23 at one end; the front end of thetorsion element 28 in the walking direction is not secured and cantherefore be moved toward the base spring 23 and away from the basespring 23.

The front end of the torsion element 28 ends in a support region 260,which is arranged approximately in the center of the length of the basespring 23. The torsion element 240 can be twisted about theprosthetic-foot longitudinal axis 230; it can likewise be bent about atorsion axis 240 extending in the medial/lateral direction such that thefront end of the torsion element 28 can be bent away from the upper sideof the base spring 23. A clear space 33 is arranged between the torsionelement 28 and the base spring 23, which clear space allows slightbending, even in the state where the front end of the torsion element 28rests on the base spring 23.

A frontal support 25, 26, 27 in the form of a leaf spring package isaffixed to the front end of the torsion element 28. Affixing can bebrought about by adhesive bonding, screwing, laminating or the like. Thelower end 250 of the frontal support 25, 26, 27 extends substantiallyparallel to the torsion element 28. From the point where it is affixedto the torsion element 28, at which the frontal support 25, 26, 27 issecured in a rigid fashion, the frontal support 25, 26, 27 extendsupwardly in an arc in the direction of a connection apparatus; which hasa proximal adapter 9 and an adjustment core 10. The upper end 140 of thefrontal support 25, 26, 27 has a straight configuration and is affixedto the proximal adapter 9 as part of the connection apparatus; thedistal end of the connection apparatus is formed by an adjustment core10 and serves for securing it to a below-knee prosthesis. In theanterior direction, the frontal support 25, 26, 27 is affixed to theproximal adapter 9; in this case too, there is a substantially rigidconnection to the frontal support 25, 26, 27.

A hydraulic damper 11, which is affixed to the proximal adapter 9 in ahinged fashion, is arranged on the side of the adjustment core 10 lyingopposite to the frontal support 25, 26, 27. The pivot axis of the uppermount extends substantially parallel to the medial/lateral axis 240. Atthe lower end of the damper 11, provision is made for a mount in amultiaxial, movable joint 34—a partial ball-and-socket joint in theexemplary embodiment—by means of which it is possible to carry out botha pivot about a medial/lateral axis and a rotation about theprosthetic-foot longitudinal axis 230. As a result of the multiaxialmount in the lower joint 34 and the rotationally symmetric embodiment ofthe movable piston or the piston rod, it is also possible for a twist tobe carried out about a vertical axis 250.

FIG. 2 shows a side view of the prosthetic foot 100 in accordance withFIG. 1, with a detailed section along the line C-C in FIG. 3. In theside view in accordance with FIG. 2, it is initially possible toidentify the substantially straight configuration of the base spring 23,which is slightly bent in the forefoot region 231. The torsion element28 as a leaf spring rests in the resting region 260 above a bufferelement 30 on the upper side of the base spring 23. The buffer element30 extends over the whole width of the torsion element 28. Beyond thebuffer element 30, a clear space 33 is provided between the torsionelement and the base spring 23. The buffer element 30 preferablyconsists of a polymer, more particularly polyurethane.

It is likewise possible to gather from FIG. 2 that the lower end 250 ofthe frontal support 25, 26, 27 is affixed to the torsion element 28. Inthe illustrated exemplary embodiment, the frontal support 25, 26, 27 ismade of three bent leaf spring elements 25, 26, 27. A clear space,which, for example, is ensured by spacer pieces 22 at the upper end 140of the frontal support 25, 26, 27, is present between the individualleaf spring elements 25, 26, 27. Spacer pieces can likewise be arrangedbetween the leaf spring elements 25, 26, 27 at the lower end 250 of thefrontal support.

The upper end of the frontal support 25, 26, 27 is affixed to theproximal adapter 9 by means of screws 14. A pressure sheet 19 foruniformly transmitting the forces of the screws 14 onto the frontal leafspring element 27 is provided between the screws 14 and the frontal leafspring element 27.

The hydraulic damper 11 is affixed to the rear region of the proximaladapter 9. The lower end of the hydraulic damper 11 is secured to theheel region 232 of the base spring 23 via a heel arm 31. The heel arm isaffixed to the base spring 23 by means of fillister screws 12. Thefillister screws 12 pass through the base spring 23, a spacer 21 forensuring the clear space 33 between the base spring 23 and the torsionelement 28, and the torsion element 28 itself and are screwed into theheel arm 31. At the same time the damping element 32 is secured to thebase spring 23 by means of the fillister screws 12. Fillister screws 13and a pressure sheet 18 are used to affix the heel spring 24 to thedamping element 32. As a result of the screwed connection, aninterchangeable embodiment of the heel spring 24 can be realized, as aresult of which there can be further adjustment to the respectiveprosthetic-foot user. Instead of a damping element 32, provision canalso be made for an adapter plate, by means of which the heel spring 24can be secured to the base spring 23. The adapter plate can serve as asupport for the hydraulic damper 11. As a result of a rounded restingsurface for the heel spring 24, it is possible to achieve increasingelevation of the resistance force since the effective length of the heelspring 24 reduces in the case of an increasing load.

FIG. 3 shows a section along the line B-B in FIG. 2. It is possible toidentify a partly cut rear view of the prosthetic foot with theadjustment core 10 and the proximal adapter 9. Two holding arms 5, 6 aremounted on the proximal adapter 9 in a hinged fashion by means of aball-and-socket joint 17 and a joint bolt 4 with a nut 15. The hydraulicdamper 11 is affixed to the two holding arms 5, 6 via screws 7, 8. Theheel arm 31 holds an adapter bolt 1, which is configured for a hingedmount of the hydraulic damper 11. The heel spring 24 forms the lowertermination of the prosthetic foot 100.

If the prosthetic foot 100 in the illustrated embodiment is used, theheel spring 24 initially comes into contact with the ground. An elasticdeformation occurs. Forces are transmitted to the base spring 23 by thescrews 13 and the damping element 32. As a result of the one-endedclamping by the screws 12 of the torsion element 28, the front end liftsoff the base spring 23 in the support region 260. The hydraulic damper11 is compressed and the frontal support 25, 26, 27 is bent backwardwith the upper end 140. As a result of the front end of the torsionelement 28 lifting and the capability thereof of twisting about theprosthetic-foot longitudinal axis 230, it is possible for a torsion andtilt movement to be carried out when the foot is set down such that thebase spring 23 and the heel spring 24 can adapt to an uneven ground.

After the heel strike, the torsion element 28 and the leaf springelements 25, 26, 27 of the frontal support bend back into their initialpositions; the hydraulic damper 11 is moved back in the direction of itsinitial position. The front, lower end of the frontal support 25, 26, 27then rests on the base spring 23 over the buffer element 30 with aninterposition of the torsion element 28. In the case of further rollovermovement, an increasing load is applied to the forefoot region 231. Theleaf spring elements 25, 26, 27 bend further, and so the curvature isincreased. The torsion element 28, the leaf spring elements 25, 26, 27and the base spring 23 then interact, wherein the base spring 23 and thetorsion element 28 as a leaf spring are connected in parallel. As aresult of only being clamped at one end, the torsion element 28 can bedisplaced along the surface of the base spring 23 when the latter isbent. The frontal support can consist of a leaf spring package made ofleaf spring elements 25, 26, 27 or of a single leaf spring element.Torsion about a vertical axis 250 is possible as a result of thestructural design of both the support of the hydraulic damper 11 and ofthe frontal support 25, 26, 27.

FIG. 4 illustrates a variant of the invention in a side view. The basicdesign corresponds to the one in accordance with FIG. 2; instead of atorsion element 28 affixed in the heel region 332 of the base spring 23,said torsion element is secured on the base spring in the forefootregion 231 in this variant. The torsion element 28 is secured on thebase spring 23 directly after the toe region thereof; in the illustratedexemplary embodiment, this is brought about by an adhesive point 233 ora weld or any other method for securing the torsion element 28 on thebase spring 23. A clear space 33 is formed between the attachment point233 and the buffer element 30, said buffer element 30 enabling atwisting movement of the torsion element 28 relative to the base spring23. The torsion element 28 extends from the attachment point 233 andafter a slight widening of the clear space 33 substantially parallel tothe base spring 23, past the buffer element 30 and from there in an arc,which opens into a straight line, to the proximal adapter 9, where it isaffixed on the upper end 140 of the frontal support 25, 26 by means ofthe screws 14. The frontal support 25, 26 is configured as anarrangement of leaf springs extending substantially in parallel; theprofile of the frontal support 25, 26 substantially corresponds to theprofile of the torsion element 28 in the direction of the proximaladapter 9 from the buffer element 30 onward. Clear spaces for enablingbending and a relative movement of the leaf springs 26, 26, 28 withrespect to one another during walking or standing are respectivelyformed between the frontal support 25, 26 and the torsion element 28.

The buffer element 30 is affixed either to the base spring 23 or to thetorsion element 28, such that if the heel is set down hard and thetorsion element 28 bends, the latter can move away from the base spring23 in a relative fashion.

The front end 250 of the frontal support 25, 26 ends approximately levelwith the buffer element 30 between the torsion element 28 and the basespring 23.

FIG. 5 illustrates a variant of the invention without frontal support.Analogously to FIGS. 1 and 2, the prosthetic foot has a forefoot region231 and a heel region 232. The base spring 23 is also made of a fibercomposite material in this case, and the explanations in respect of thebase spring 23 and the torsion element 28 arranged above the base spring23 apply correspondingly. A clear space 33 is arranged between thetorsion element 28 and the upper side of the base spring 23. Acushioning element 300 for preventing disturbing noises in the case of arelative movement between the torsion element 28 and the base spring 23can be arranged at the front end of the torsion element 28.

At its rear end, the torsion element 28 is secured at one end to therear end of the base spring 23 in the heel region 232 by means of thescrews 12. Attachment occurs exclusively in the heel region 232 of thebase spring 23. The connection apparatus of proximal adapter 9 andadjustment core 10 is, in the walking direction, arranged in front ofthe attachment elements 12 on the torsion element 30 and optionally hasa wedge placed therebeneath in order to simplify the setting of a tiltand thereby simplify an adjustment of the alignment of upper prosthesiscomponents. By directly linking the connection apparatus to the torsionelement 28 and the one-ended mount thereof, the upper connection means(not illustrated) can also be displaced or tilted about the longitudinalaxis of the foot, in addition to a parallel collection of the torsionelement 28 with the base spring 23. The torsion element 28 can likewiseserve as an additional spring and bring about a parallel connectionbetween the base spring 23 and the torsion element 28.

The invention claimed is:
 1. A prosthetic foot, comprising: a basespring having a forefoot region and a heel region; a heel springarranged on the base spring; a damping element arranged between the basespring and the heel spring; a connection apparatus arranged above thebase spring and configured to connect the prosthetic foot to aprosthesis; a torsion element; a frontal support having an upper endconnected to the connection apparatus and a lower end secured to thetorsion element; wherein the torsion element is configured to twistabout the prosthetic-foot longitudinal axis, and is configured as a leafspring apparatus that is secured at only one end to the base spring,either in the heel region or in the forefoot region, and the lower endof the frontal support having a free end, which terminates at a supportarea positioned approximately in a center of a length of the basespring; wherein during normal use of the prosthetic foot, a free end ofthe torsion element contacts the base spring at least when the forefootregion is set down in contact with a support surface and during rollover to provide force transmission from the base spring to the frontalsupport.
 2. A prosthetic foot, comprising; a base spring with a forefootregion and a heel region; a connection apparatus, arranged above thebase spring, for affixing the prosthetic foot to a prosthesis; a frontalsupport; a torsion element; a heel spring is arranged on the basespring; a damping element is arranged between the base spring and theheel spring; wherein the connection apparatus is secured to the torsionelement with the frontal support, the torsion element being configuredto twist about the prosthetic-foot longitudinal axis, which torsionelement is configured as a leaf spring apparatus, secured at one end tothe base spring in the heel region, and a lower end of the frontalsupport having a free end, which terminates at a support area positionedapproximately in a center of a length of the base spring; wherein duringnormal use of the prosthetic foot, a free end of the torsion elementcontacts the base spring at least when the forefoot region is set downin contact with a support surface and during roll over to provide forcetransmission from the base spring to the frontal support.
 3. Theprosthetic foot as claimed in 2, wherein the torsion element can betwisted about a medial/lateral axis.
 4. The prosthetic foot as claimedin claim 1, wherein a clear space is formed between the base spring andthe torsion element.
 5. The prosthetic foot as claimed in claim 1,wherein the torsion element can be twisted about a medial/lateral axis.6. The prosthetic foot as claimed in claim 1, wherein the frontalsupport is configured as a spring or spring package.
 7. The prostheticfoot as claimed in claim 1, wherein the frontal support is configured insuch a way that it can be twisted about a vertical axis.
 8. Theprosthetic foot as claimed in claim 1, wherein a damping element or aresilient element, which is supported on the base spring or on thetorsion element in the heel region of the base spring.
 9. The prostheticfoot as claimed in claim 8, wherein the damping element is configured asa fluid damper.
 10. The prosthetic foot as claimed in claim 8, whereinthe damping element has at least one multi-axially movable joint. 11.The prosthetic foot as claimed in claim 2, wherein a clear space isformed between the base spring and the torsion element.
 12. A prostheticfoot, comprising: a base spring with a forefoot region and a heelregion; a connection apparatus arranged above the base spring andconfigured to connect the prosthetic foot to a prosthesis; a torsionelement configured to twist about a longitudinal axis of the prostheticfoot and having a leaf spring construction, only one end of the torsionelement being connected to either the heel region or the forefoot regionof the base spring; a frontal support having an upper end connected tothe connection apparatus and a lower end connected to the torsionelement, wherein the lower end of the frontal support having a free end,which terminates at a support area positioned approximately in a centerof a length of the base spring; a damping element or a resilientelement, which is supported on the base spring or on the torsion elementin the heel region of the base spring, the damping element beingconfigured as a fluid damper; wherein during normal use of theprosthetic foot, a free end of the torsion element contacts the basespring at least when the forefoot region is set down in contact with asupport surface and during roll over to provide force transmission fromthe base spring to the frontal support.
 13. The prosthetic foot asclaimed in claim 12, wherein a space is formed between the base springand the torsion element.
 14. The prosthetic foot as claimed in claim 12,wherein the torsion element can be twisted about a medial/lateral axis.15. A prosthetic foot, comprising: a base spring having a forefootregion and a heel region; a heel spring arranged on the base spring; adamping element arranged between the base spring and the heel spring; aconnection apparatus arranged above the base spring and configured toconnect the prosthetic foot to a prosthesis; a torsion element; afrontal support having an upper end connected to the connectionapparatus and a lower end secured to the torsion element; a dampingelement or a resilient element, which is supported on the base spring oron the torsion element in the heel region of the base spring, thedamping element having at least one multi-axially movable joint; whereinthe torsion element is configured to twist about the prosthetic-footlongitudinal axis, and is configured as a leaf spring apparatus that issecured at only one end to the base spring, either in the heel region orin the forefoot region, and the lower end of the frontal support havinga free end, which terminates at a support area positioned approximatelyin a center of a length of the base spring; wherein during normal use ofthe prosthetic foot, a free end of the torsion element contacts the basespring at least when the forefoot region is set down in contact with asupport surface and during roll over to provide force transmission fromthe base spring to the frontal support.
 16. The prosthetic foot asclaimed in claim 15, wherein a space is formed between the base springand the torsion element.
 17. The prosthetic foot as claimed in claim 15,wherein the torsion element can be twisted about a medial/lateral axis.18. The prosthetic foot as claimed in claim 15, wherein the frontalsupport is configured as a spring or spring package.
 19. The prostheticfoot as claimed in claim 15, wherein the frontal support is configuredin such a way that it can be twisted about a vertical axis.